Well it was sealed, but it was over 6 years old so I have chucked it. It smelt good and beery when I opened it but looked really dark. Best not to risk it. I'll treat myself to a fresh bottle to replace it!
Only last week I tipped a large bottle of Becks down the sink - found it in the back of a cupboard with best before some date in 2013. Mind you it smelt OK!